A teleconference is the live exchange of information among several persons and machines (also called endpoint devices) remote from one another but linked by a communications system based on a communications network such as Public Telephone Network, Integrated Services Digital Network, Internet Protocol Network, etc. The communications system may support the teleconference by providing one or more of the following: audio, video, and/or data services by one or more means, such as telephone, computer, telegraph, teletypewriter, radio, and television.
Audio or video (A/V) signals in a media stream (audio, video or both) are usually called as nuisance if they can be perceived by the users but are actually not relevant to the teleconference or can cause unpleasant feeling or confusion. The nuisance may also be called as nuisance to the teleconference. The nuisance may come from the signal capturing process (i.e. from the camera and the microphone). For example, the nuisance can be a purely audio noise signal. Various techniques have been proposed to handle nuisances in the teleconference. For example, U.S. Pat. No. 7,269,252 B2, “METHOD AND APPARATUS FOR IMPROVING NUISANCE SIGNALS IN AUDIO/VIDEO CONFERENCE” discloses a system to allow a conferee being defined as a nuisance source to respond to an automatic nuisance decision of a Multipoint Control Unit (MCU). For example, a conferee placing a conference on hold may generate on hold music, which may be identified by a nuisance detector. The nuisance detector sends an indication of the nuisance condition to a control unit in the MCU. The control unit mutes the signal coming from this conferee and sends an Interactive Voice Response (IVR) message to the conferee. The message may inform the conferee that he has been muted and requests the conferee for example to press one of a plurality of touch tone keys depending on his situation. For instance, the conferee can select particular keys if he is returning from the hold condition, if he is experiencing a noisy line/environment and needs to reduce the sensitivity of the nuisance detector algorithm, or if he wishes to disable the nuisance detector algorithm.